While Martin Luther King Jr. is not with us any more, his dream is alive and well. ... 50 years later we refuse to forget or ignore the sermon of the Lincoln Memorial, Carro writes.

"I have a dream," preached the Rev. Martin Luther King Jr. from the stairs of the Lincoln Memorial 50 years ago. "It is a dream deeply rooted in the American dream. I have a dream that one day this nation will rise up and live out the true meaning of its creed: We hold these truths to be self-evident: that all men are created equal."

As a dreamer, he is not alone.

Almost 50 years ago too a "dreamer" of other sorts, John Lennon, wrote the now famous song Imagine:

"Imagine there's no heaven / It's easy if you try / No hell below us / Above us only sky / Imagine all the people / Living for today"

"Imagine there's no countries / It isn't hard to do / Nothing to kill or die for / And no religion too / Imagine all the people / Living life in peace..."

"You may say I'm a dreamer / But I'm not the only one / I hope someday you'll join us / And the world will be as one."

Joseph, Pharaoh, Jacob, Nebuchadnezzar, Paul, Constantine, Descartes, Abraham Lincoln, Albert Einstein, all of them were dreamers in their own way, as many others.

Dreams are the compost, the fertilizer, of our human existence. Our full humanity is displayed in our dreams. We are all dreamers.

The question is not so much, "What are these dreams that we all have?" but, "What do we do with them?"

There are people like Lennon who cast utopian dreams, blue unicorns that only fly in their convoluted, feverish minds.

But there is another kind of dreamer – one who casts realistic, much needed dreams of what is possible. Martin Luther King Jr. is one of them.

"I have a dream that one day on the red hills of Georgia the sons of former slaves and the sons of former slave owners will be able to sit down together at the table of brotherhood."

"I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character. I have a dream today."

"I have a dream that one day, down in Alabama, with its vicious racists, with its governor having his lips dripping with the words of interposition and nullification; one day right there in Alabama, little black boys and black girls will be able to join hands with little white boys and white girls as sisters and brothers."

These were King's possible dreams.

These possible dreams are the ones that bother and trouble those who profit from the disadvantaged.

They try to equate Lennon and King as if all of these dreams were only "dreams."

But when they cannot achieve their manipulative intention, they resort to violence.

Many times those who dream possible dreams pay for their dreaming with their lives. A coward thought that killing King would kill his dream.

Dreams can be forgotten, dreams can be ignored, but dreams cannot be killed.

When our Lord was raised on the cross, there was little hope that his death would transform humanity.

But when resurrection happened, our perishable bodies put on imperishability, our mortal bodies put on immortality, and the saying was fulfilled: "Death has been swallowed up in victory" (1 Corinthians 15:54).

"This is our hope. This is the faith that I go back to the South with. With this faith we will be able to hew out of the mountain of despair a stone of hope. With this faith we will be able to transform the jangling discords of our nation into a beautiful symphony of brotherhood. With this faith we will be able to work together, to pray together, to struggle together, to go to jail together, to stand up for freedom together, knowing that we will be free one day."

King's dream is still marching on. The dream is still not reached.

There is still too much cacophony that overrides the "symphony of brotherhood" that King dreamed of hearing in the red hills of Georgia, down in Alabama, all over our nation and the whole world.

While King is not with us any more, his dream is alive and well. Not fully realized and a work in progress, to be sure, but 50 years later we refuse to forget or ignore the sermon of the Lincoln Memorial.

In this day, as we remember King, we commit to the dream anew. So help us God.

Daniel Carro, originally from Argentina, is professor of divinity at The John Leland Center for Theological Studies in Arlington, Va. He is also Latino Kingdom Advance Ambassador with the Virginia Baptist Mission Board. This column also appeared on the John Leland Center's blog.